Friday, August 01, 2008

Additional Cardiac Monitoring for Patients on Mitoxantrone - from Heartwire — a professional news service of WebMD

Sue Hughes

July 30, 2008 — The FDA has issued an alert informing healthcare professionals about additional recommendations for cardiac monitoring of patients with multiple sclerosis (MS) who are treated with mitoxantrone (marketed as Novantrone and as generics) [1].

In 2005, the labeling for mitoxantrone was changed to recommend that left ventricular ejection fraction (LVEF) be evaluated before initiating treatment and before administering each dose of mitoxantrone to patients with MS. These changes were established in response to postmarketing and case reports in the medical literature that described decreases in LVEF or frank congestive heart failure in patients with MS who had received cumulative doses of mitoxantrone that were lower than 100 mg/m2.

Since that time, the FDA has received information from a postmarketing safety study that demonstrated poor adherence to these recommendations in clinical practice. This study used insurance-claims data and medical-record reviews to examine cardiac monitoring patterns in clinical practice. In this study, it was noted that four patients developed congestive heart failure 4 to 17 months after completing therapy with mitoxantrone.

Given the potential severity of cardiotoxicity and evidence suggesting poor adherence to the recommendations for monitoring cardiac function, the FDA is currently working with the manufacturers of mitoxantrone to remind healthcare professionals of the importance of adhering to the recommendations for patients with MS who are treated with mitoxantrone.

In addition, the FDA and the manufacturers are now advising that all patients with MS who have finished treatment with mitoxantrone receive yearly quantitative LVEF evaluations to detect late-occurring cardiac toxicity.

The FDA has issued the following recommendations for patients treated with mitoxantrone.

For All Patients

Assess signs and symptoms of cardiac disease with a history, physical examination, and ECG before initiating therapy with mitoxantrone. Perform a baseline quantitative evaluation of LVEF.

For Patients With MS

Patients with a baseline LVEF below the lower limit of normal should not be treated with mitoxantrone.

Patients should be assessed for cardiac signs and symptoms with a history, physical examination, and ECG before each dose. Patients should undergo a quantitative reevaluation of LVEF before each dose, using the same methodology for each assessment. Additional doses of mitoxantrone should not be administered to patients who have experienced either a drop in LVEF to below the lower limit of normal or a clinically significant reduction in LVEF during mitoxantrone therapy. Patients should not receive a cumulative mitoxantrone dose greater than 140 mg/m2. Patients should undergo yearly quantitative LVEF evaluations after stopping mitoxantrone to monitor for late-occurring cardiotoxicity, using the same methodology that was used for assessments that were done during treatment.

For Patients With cancer

The possible danger of cardiac effects in patients previously treated with daunorubicin or doxorubicin should be considered when weighing the benefits and risks of mitoxantrone. The presence or history of cardiovascular disease, previous or concomitant radiotherapy to the mediastinal/pericardial area, previous therapy with other anthracyclines or anthracenediones, or the concomitant use of other cardiotoxic drugs might increase the risk of cardiac toxicity. LVEF should be monitored regularly after the initiation of therapy in patients with these risk factors.

From Medical News TodayResearch published in Nature Neuroscience , electronic publication ahead of print) has shown that adult stem cells in mice that are developing into nerve cells can be redirected to turn into myelin -making cells by changing a single gene . This type of research may some day help repair the damage to myelin which occurs in multiple sclerosis (MS).

In people with MS the immune system can attack both myelin and myelin making cells (oligodendrocytes). Limiting the number of myelin making cells impairs the capacity to repair the damage to myelin. One potential treatment option currently being investigated involves encouraging immature stem cells that reside in the adult brain, called neural stem cells, to move to areas of damage and repair myelin.

When neural stem cells are grown in the laboratory scientists have been able to reprogramme them to develop into several different types of brain cells, including oligodendrocytes. This latest research which took place in The Salk Institute for Biological Studies in California sought to determine if it would be possible to repeat these experiments in the brain.

A gene called Asc1 which is associated with oligodendrocyte development was introduced into the stem cells in the brain and caused neural stem cells to develop into oligodendrocytes.

This study confirms that adult stem cells in the brain retain their ability to be converted to certain other types of brain cells. Further research is needed to determine the significance of these finding to myelin repair in people with MS.

Dr Laura Bell at the MS Society said: 'Finding a way to cause stem cells which are already present in the brain to repair damaged myelin is an attractive potential treatment option for people with MS. This is early research but it is an important step and we look forward to seeing how the work progresses.'